This is equal to the sine of theta.

侧可以同时乘以重力的大小。

This right here is 90 minus theta.

那么上面这个角是多少。

And that's why it's cosine of theta.

因 相等。

So this is going to be equal to the sine of theta.

侧可以同时乘以重力的大小。

So this is 90 minus theta degrees.

这个也是90-θ度。

A change from alpha wave drowsiness to lower frequency theta brain waves signify early sleep.

从α波睡意到较频率的脑电波的变化表示早睡。

There are three frequencies that we need to understand, Beta frequency, Theta frequency, and Alpha frequency.

我们需要理解三种频率，贝塔频率，西塔频率法频率。

This too will be 90 minus theta degrees.

再看如何求出这个角。

So the factor by which the slice gets squished down in this direction is exactly cosine of theta.

因，切片 在这个方向上被压扁的因素正是 theta 的余弦。

Remember, the mass ratio of our blocks determines this angle theta in the analogy.

请记住，我们块的质量比决定了类比中的角度 θ。

And they observed an increase in so-called theta activity.

他们观察到所谓的 theta 活动有所增加。

Sine theta equals opposite over hypotenuse.

正弦θ等于对边除以斜边。

Likelihood of theta given D, or gamma.

给定 D, θ 的概率, 或伽马。

I'm gonna use sine of theta, oh sorry, sine of phi.

我要使用正弦 theta， 哦抱歉，正弦 phi。

Let's call the angle between this momentum line and the vertical " theta" .

我们将这条动量线与垂直线之间的角度称为“theta”。

And now for the Y direction we can use the definition of sine of theta.

现在对于 Y 方向，我们可以使用正弦函数的定义。

Theta is, how might you proceed?

，您会如何进行？

Cosine theta equals adjacent over hypotenuse.

cosine theta 等于相邻在斜边上。

That's where the sine theta comes in – its maximum value is 1, when theta is 90 degrees.

这就是正弦 theta 的用武之地—— 当 theta 为 90 度时，它的最大值为 1。

And so pi represents your beliefs on theta.

所以π代表你对θ的信念。